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            <h2 class="title" style="clear: both"><a id="envset_lg_max"></a>DB_ENV-&gt;set_lg_max()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;set_lg_max(DB_ENV *dbenv, u_int32_t lg_max);  </pre>
      <p>
         Sets the maximum size of a single file in the log, in bytes.  Because
         <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a>  file offsets are
         unsigned four-byte values, the set value may not be larger than the
         maximum unsigned four-byte value.
    </p>
      <p>
         When the logging subsystem is configured for on-disk logging, the
         default size of a log file is 10MB.
    </p>
      <p>
         When the logging subsystem is configured for in-memory logging, the
         default size of a log file is 256KB.  In addition, the configured log
         buffer size must be larger than the log file size.  (The logging
         subsystem divides memory configured for in-memory log records into
         "files", as database environments configured for in-memory log records
         may exchange log records with other members of a replication group,
         and those members may be configured to store log records on-disk.) 
         When choosing log buffer and file sizes for in-memory logs,
         applications should ensure the in-memory log buffer size is large
         enough that no transaction will ever span the entire buffer, and avoid
         a state where the in-memory buffer is full and no space can be freed
         because a transaction that started in the first log "file" is still
         active.
    </p>
      <p>
         See <a href="../../programmer_reference/log_limits.html" class="olink">Log File Limits</a> for
         more information.
    </p>
      <p>
         The database environment's log file size may also be configured
         using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of the entry
         in that file is a single line with the string "set_lg_max", one or
         more whitespace characters, and the size in bytes. Because the
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the database environment is opened,
         it will silently overrule configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;set_lg_max()</code> method configures a database environment,
         not only operations performed using the specified 
         <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;set_lg_max()</code> method may be called at any time during the
         life of the application.
    </p>
      <p>
         If no size is specified by the application, the size last specified
         for the database region will be used, or if no database region
         previously existed, the default will be used.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;set_lg_max()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idp53052536"></a>Parameters</h3>
            </div>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idp53053136"></a>lg_max</h4>
              </div>
            </div>
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          <p>
                          The <span class="bold"><strong>lg_max</strong></span> parameter is the size of a
                          single log file, in bytes.
                     </p>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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              <h3 class="title"><a id="idp53056232"></a>Errors</h3>
            </div>
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        <p>
                         The <code class="methodname">DB_ENV-&gt;set_lg_max()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
                    </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp53063288"></a>EINVAL</h4>
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          <p>
                              If the size of the log file is less than four
                              times the size of the in-memory log buffer;
                              the specified log file size was too large; or
                              if an invalid flag value or parameter was
                              specified.
                         </p>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp53062208"></a>Class</h3>
            </div>
          </div>
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        <p>
                    <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>, 
                    <a class="link" href="logc.html" title="The DB_LOGC Handle">DB_LOGC</a>, 
                    <a class="link" href="lsn.html" title="Chapter 7.  The DB_LSN Handle">DB_LSN</a> 
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp53052704"></a>See Also</h3>
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        <p>
                     <a class="xref" href="lsn.html#loglist" title="Logging Subsystem and Related Methods">Logging Subsystem and Related Methods</a> 
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